Arrangement of a relay on a plug base

ABSTRACT

In order to seal the plug-in region between a relay and a plug base, a peripheral sealing ring is integrally formed in one piece on the dimensionally stable plastic of one part using the two-component injection-molding process. The sealing ring is elastically deformed by latching elements which engage one in the other, thereby providing the desired sealing of the arrangement.

BACKGROUND OF THE INVENTION FIELD OF THE INVENTION

The present invention is directed to relays that are plugged into plugbases and, more specifically, to a combination relay and plug basewhereby the connection between the relay and the plug base is waterproofand secure. In this context, relay is also understood to mean aso-called relay module, in which further circuit elements, such asresistors and diodes with the associated conductor tracks, are arrangedin the housing in addition to the actual relay system.

A large number of possibilities have already been described for thesealing of relay housings, for example the potting of housing gaps withliquid and subsequently curable potting compound. It is also known (DE43 37 505 C1) to coat wall regions between base or baseplate, on the onehand, and cap, on the other hand, with an elastomer layer using thetwo-component injection-molding process and thus to achieve the desiredsealing when the housing parts are pressed onto one another.

If, however, a relay is inserted into a plug base, as is customary inmotor vehicles, for example, then the plug connection between relay andplug base remains unprotected, even if the relay itself is sealed. Sincesuch plug bases, particularly in the engine compartment of motorvehicles, are frequently exposed to severe fouling or moisture, it hasbeen customary to date to insert additional sealing rings between relayand plug base in order to protect the plug connection.

EP 0 400 434 B1 furthermore discloses, for the connection of anelectrical module, in particular of a relay, using an additionalencasing housing, into which the relay is inserted. The encasing housinghas a seal on two sides, namely, on the one hand, in the region of theplug connection, where a radial seal is provided in a region of overlapbetween plug base and encasing housing, and, on the other hand, on theopposite, open housing side, where a closure cover is tightly insertedby means of a sealing ring that is introduced. However, such an encasinghousing causes a considerable additional outlay in terms of productionand materials, quite apart from the large space requirement.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a simple seal between aplug-in relay and the associated plug base, the seal requiring onlyslight structural changes and managing without additional individualparts, such as sealing rings and the like, during plug-in mounting.

According to the invention, this aim is achieved in that at least one ofthe two housings is composed of a dimensionally stable thermoplasticand, in an edge zone which faces the other housing and encloses the plugpins and plug-in openings, carries a sealing ring made of an elastomerand integrally formed in one piece, and in that the two housings areconnected to one another in a positively locking and/or force lockingmanner by means of wall elements engaging one over the other, withelastic deformation of the sealing ring.

Since the housing caps of such relays and also the housings of plugholders are generally produced from a dimensionally stable thermoplasticmaterial in any case, the additional integral forming of athermoplastic, elastomeric sealing ring using the two-componentinjection-molding process causes only a slight additional outlay interms of production. The respective other housing, in other words theone which does not carry the sealing ring, remains completely unchangedin any event. If the sealing ring is integrally formed on the plug base,the cap of the relay housing could even be composed of metal.

Depending on the individual conditions, the sealing ring may either beintegrally formed on the relay cap and form its lower edge, or it may berecessed into the planar top side of the plug base opposite the edge ofthe relay cap. Alternatively, said ring may be integrally formed as aradial seal in the region of overlap between plug base and relay cap onone or the other part.

In an embodiment, the combination relay/plug base includes a relay witha relay housing which includes a bottom side from which a plurality ofplug pins project to connect the relay housing to the plug base and theplug base also comprises a housing with a top side having a plurality ofplug openings for accommodating the plug pins of the relay. The bottomside of the relay housing and the top side of the base housing engageeach other at a common edge zone which encloses the plug pins of therelay that are received in the plug openings of the base. The edge zoneaccommodates a sealing ring which engages both the relay housing and thebase housing to provide a sealed enclosure of the plug pins and plugopenings. The relay housing and the base housing are positivelyconnected to one another by cooperating locking wall elements whichresult in an elastic deformation of the sealing ring.

In an embodiment, the relay housing includes a cap structure whichencloses the bottom side of the relay housing and has a lower edge. Thesealing ring is integrally formed on the lower edge of the cap in onepiece and the cap is latched onto the base with cooperating latchingelements on the cap and the base which causes the sealing ring to bedeformably pressed between the edge of the cap and the top of the basehousing.

In another embodiment, the relay housing also includes a cap on the topside of the base housing which includes a recess which surrounds theplug opening. The sealing ring is injection-molded into the recess and,when the cap is latched onto the base housing, the lower edge of the capis pressed into the sealing ring thereby providing a sealed connectionwith protects the plug pins and plug openings from the environment.

In an embodiment, the sealing ring is injection molded in one piece intothe edge zone disposed between the cap of the relay and the top side ofthe base housing.

In an embodiment, the sealing ring is injection-molded in one piece ontothe top side of the base housing.

In an embodiment, the base housing is further characterized as includingan upwardly protruding collar that mateably receives the bottom side ofthe relay housing when the relay is connected to the base. A sealingring is injection-molded in one piece into the bottom side of the relayhousing and is deformably pressed between the bottom side of the relayhousing and the top side of the base when the relay and plug base areconnected together.

In an embodiment, the top side of the base housing comprises an upwardlyprotruding collar and the relay housing comprises a cap with adownwardly protruding lower edge. The lower edge of the cap is matablyreceived within the collar of the base housing and the sealing ring isinjection-molded in one piece onto an inside wall of the collar of thebase housing and provides a sealing engagement between the cap of therelay housing and the collar of the plug base housing.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is explained in more detail below using exemplaryembodiments with reference to the drawings, in which

FIG. 1 is an elevational partial-sectional view of a relay housing witha plug base made in accordance with the present invention;

FIG. 2 is an enlarged partial-sectional view of the relay housing andplug base shown in FIG. 1;

FIG. 3 is a sectional view taken substantially along line III--III ofFIG. 2;

FIG. 4 is an elevational partial-sectional view of a second embodimentof a relay housing and plug base made in accordance with the presentinvention;

FIG. 5 is a sectional view taken substantially along line V--V of FIG.4;

FIG. 6 is an elevational partial-sectional view of a third embodiment ofa relay housing and plug base made in accordance with the presentinvention;

FIG. 7 is a sectional view taken substantially along line VII--VII ofFIG. 6;

FIG. 8 is a sectional view of a fourth embodiment of a plug base made inaccordance with the present invention; and

FIG. 9 is an elevational partial-sectional view of a fifth embodiment ofa relay housing and plug base made in accordance with the presentinvention.

It should be understood that the drawings are not necessarily to scaleand that the embodiments are sometimes illustrated by graphic symbols,phantom lines, diagrammatic representations and fragmentary views. Incertain instances, details which are not necessary for an understandingof the present invention or which render other details difficult toperceive may have been omitted. It should be understood, of course, thatthe invention is not necessarily limited to the particular embodimentsillustrated herein.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

FIG. 1 shows the arrangement of a relay 1 on a plug base 2. The relayhas a housing having a housing cap 11 and a baseplate 12, in which plugpins 13 are anchored. These plug pins are designed as blade terminals,as is evident in FIG. 3.

The plug base 2 has a housing 21 having chambers 22 in which plugsockets 23 are arranged. The chambers 22 open to the top side of thehousing 21 in plug-in openings 24, through which the plug pins 13 of therelay are introduced. Connecting wires 25 are passed out at theunderside of the housing 21, which wires are connected to the plugsockets 23 in the interior in a manner that is not illustrated.

In order to seal the plug connection between the relay 1 and the plugbase 2, a sealing ring 14 in the form of a web is integrally formed onthe housing cap 11, to be precise on the lower edge thereof. Thissealing ring 14 is composed of an elastomeric thermoplastic, while thehousing cap 11 is otherwise composed of a dimensionally stablethermoplastic. In this way, it is possible to produce the housing capwith the sealing ring in one piece using a two-componentinjection-molding process. In order to produce the necessary contactpressure on the sealing ring 14, the housing cap is additionallyprovided with latching lugs 15, which latch into retaining tabs 26 ofthe plug base. As can be seen in FIG. 1, the sealing ring 14 iselastically deformed by this latching, thereby producing the desiredsealing of the two housings.

A modified embodiment is shown in FIGS. 4 and 5. The structure of therelay 1 and of the plug base 2 is largely the same as in FIG. 1.However, the sealing is effected in a complementary manner in this case.Instead of the sealing ring 14 on the relay cap, a sealing ring 27 isnow injection-molded in a recessed manner into the planar top side ofthe plug base housing 21. The lower edge 16 of the housing cap 11 isforced into the sealing ring 27 by the latching of the latching lugs 15in the retaining tabs 26, thereby achieving the desired sealing.

FIGS. 6 and 7 show a further modification. In this case, the relay cap11 includes a collar 17, which is integrally formed downwards, over thebase housing 21, which carries a radial sealing ring 28 which isinjection-molded in a peripheral manner into a depression in the sidewall. The elastic deformation of the sealing ring 28 is produced by theforce-locking fitting of the collar 17 onto the base housing 21. FIG. 6also shows, by way of suggestion, that annular seals 29 are provided inthe base housing 21 for the tight lead-through of each of the connectingwires 25. These annular seals 21 can be integrally formed in one pieceon the base housing 21 using a two-component injection-molding processin the same way as the radial sealing rings 28.

FIG. 8 shows a plan view of a modified base housing 31, which can beprovided with a radial seal, in this case with a sealing ring 38, in thesame way as the rectangular housing shown in FIG. 7. This connectorhousing would be suitable for a relay which likewise had acorrespondingly round cross section.

FIG. 9 shows a further modification of a relayplug base arrangementsimilar to FIG. 6. In this case, the base housing 21 engages with acollar 30, which is integrally formed upwards over the cap 11 of therelay. A sealing ring 18 is provided in the region of overlap betweenthe collar 30 and the cap 11, which sealing ring is in turn made ofelastomeric material and connected in one piece to the relay cap 11using the two-component injection-molding process. Instead of thesealing ring 18, as is shown on the left-hand side of the cap 11 in FIG.9, it is also possible to use a sealing ring 19 in accordance with theillustration on the right-hand side of FIG. 9. This sealing ring 19additionally engages in a roof-like manner over the upper edge of thecollar 30 and thus prevents water or dirt from being able to settle inthe gap between relay housing cap 11 and base collar 30. Both the relay1 and the plug base 2 are otherwise constructed as in the rest of theexamples.

From the above description, it is apparent that the objects of thepresent invention have been achieved. While only certain embodimentshave been set forth, alternative embodiments and various modificationswill be apparent from the above description to those skilled in the art.These and other alternatives are considered equivalents and within thespirit and scope of the present invention.

I claim:
 1. A combination of an electrical component mounted onto a plugbase, the combination comprising:the component comprising a componenthousing, the component housing comprising a bottom side from which aplurality of parallel plug pins project to connect the component housingto the plug base, the component housing further comprising a continuouscollar that extends past the bottom side of the relay housing andparallel to the plug pins, the collar housing an inside surface, theplug base comprising a base housing, the base housing comprising a topside with a plurality of plug openings for accommodating the plug pinsof the component, the plug base further comprising an outer sidewallwith a continuous recess disposed therein, the continuous recess of thesidewall being integrally connected to an injection molded continuoussealing ring, the collar of the relay housing matably receiving the basehousing therein whereby the continuous sealing ring is deformablytrapped between the recess of the sidewall of the base housing and theinside surface of the collar of the component housing, the relay housingand the base housing being positively connected to one another bycooperating locking wall elements resulting in an elastic deformation ofthe sealing ring.
 2. The combination of claim 1 whereinthe cap comprisesat least one latching element, the base housing comprises at least onelatching element, the latching elements of the cap and the plug baseinterlocking with one another to positively lock the component into therecess of the plug base and to press the inside surface of the collarinto the sealing ring.
 3. The combination of claim 1 wherein the relayhousing is fabricated from dimensionally stable thermoplastic material.4. The combination of claim 1 wherein the base housing is fabricatedfrom dimensionally stable thermoplastic material.
 5. A combination of anelectrical component mounted onto a plug base, the combinationcomprising:the component comprising a component housing fabricated froma thermoplastic material, the component housing comprising a cap whichsurrounds a bottom side of the component housing from which a pluralityof parallel plug pins project to connect the component to the plug base,the plug base comprising a base housing, the base housing comprising atop side with a plurality of plug openings for accommodating the plugpins of the component the top side of the base housing comprising acollar that extends towards the component, housing and which is parallelto the plug pins, the cap comprising a continuous lower edge, the loweredge of the cap being integrally connected to a one-piece continuoussealing ring, the lower edge of the cap being matably received withinthe collar and engaging the top side of the base housing so that thelower edge of the cap and sealing ring surrounds the plug pins and plugopenings and so that the collar of the top side of the base housingsurrounds the lower edge of the cap, the relay housing and the basehousing being positively connected to one another by cooperating lockingwall elements resulting in an elastic deformation of the sealing ringbetween the lower edge of the cap and the top side of the base housing.6. A combination of an electrical component mounted onto a plug base,the combination comprising:the component comprising a component housingfabricated from a thermoplastic material, the component housingcomprising a cap which surrounds a bottom side of the housing from whicha plurality of parallel plug pins project to connect the componenthousing to the plug base, the plug base comprising a base housing, thebase housing comprising a top side with a plurality of plug openings foraccommodating the plug pins of the component, the cap comprising a loweredge, the top side of the base housing comprising a recess thatsurrounds the plug openings, the recess being integrally connected to aone-piece sealing ring, the top side of the base housing furthercomprising a continuous collar that extends towards the componenthousing and which is disposed parallel to the plug pins, the componenthousing and the base housing being positively connected to one anotherby cooperating locking wall elements resulting in an elastic deformationof the sealing ring between the lower edge of the cap and the recess ofthe top side of the base housing and resulting in the lower edge of thecap being matably received within the collar and the collar surroundingthe lower edge of the cap.
 7. A combination of an electrical componentmounted onto a plug base, the combination comprising:the electricalcomponent comprising a component housing fabricated from a thermoplasticmaterial, the component housing comprising a cap which surrounds abottom side of the component housing from which a plurality of parallelplug pins project to connect the component housing to the plug base, theplug base comprising a base housing, the base housing comprising a topside with a plurality of plug openings for accommodating the plug pinsof the component, the cap comprising a lower outer surface, the lowerouter surface of the cap comprising a continuous recess, the recessbeing integrally connected to a one-piece sealing ring, the top side ofthe base housing comprises a collar disposed parallel to the plug pinsand that matably receives the lower outer surface of the cap, the collarcomprising an inside surface, the cap of the component housing engagingthe top side of the base housing so that the inside surface of thecollar of the base housing, the lower outer surface of the cap andsealing ring surround the plug pins and plug openings, the componenthousing and the base housing being positively connected to one anotherby cooperating locking wall elements resulting in an elastic deformationof the sealing ring between the lower outer surface of the cap andinside surface of the collar of the base housing.
 8. A method ofmanufacturing an electrical component mounted onto a plug base, themethod comprising the following steps:providing a plug base comprising abase housing, the base housing comprising a top side with a plurality ofplug openings, the base housing comprising an upwardly protruding andcontinuous collar, providing a component comprising a plurality of plugpins, injection molding a component housing from a thermoplasticmaterial having a lower edge for being matably received within thecollar of the plug base and injection molding a continuous sealing ringfrom an elastomeric material onto the lower edge of the componenthousing, inserting the component through the lower edge of the componenthousing so that the plug pins extend outward from the component housing,inserting the component housing and component into the collar of theplug housing so that the plug pins are received in the plug openings andthe continuous sealing ring is deformably trapped between the lower edgeof the component housing and the plug base.
 9. A method of manufacturingan electrical component mounted onto a plug base, the method comprisingthe following steps:providing a plug base comprising a base housing, thebase housing comprising a top side with a plurality of plug openings,the base housing comprising an upwardly protruding and continuous collarwith a continuous inside surface, providing a component comprising aplurality of plug pins, injection molding a component housing from athermoplastic material having a continuous lower outer surface for beingmatably received within the collar of the plug base, the continuouslower outer surface having a continuous recess disposed therein, andinjection molding a continuous sealing ring from an elastomeric materialinto the recess of the lower outer surface of the component housing,inserting the component through the lower edge of the component housingso that the plug pins extend outward from the component housing,inserting the component housing and component into the collar of theplug housing so that the plug pins are received in the plug openings andthe continuous sealing ring is deformably trapped between the recess ofthe lower outer surface of the component housing and the inside surfaceof the collar of the plug base.
 10. A method of manufacturing anelectrical component mounted onto a plug base, the method comprising thefollowing steps:injection molding a base housing for a plug base from athermoplastic material, the base housing comprising a top side with aplurality of plug openings, a continuous recess that surrounds the plugopenings and an upwardly protruding and continuous collar that surroundsthe recess, and injection molding a continuous sealing ring from anelastomeric material into the recess of the base housing, providing acomponent comprising a plurality of plug pins and a component housinghaving a lower edge for being matably received within the collar of thebase housing, inserting the component housing and component into thecollar of the plug housing so that the plug pins are received in theplug openings and the continuous sealing ring is deformably trappedbetween the lower edge of the component housing and the recess of theplug base.
 11. A method of manufacturing an electrical component mountedonto a plug base, the method comprising the following steps:injectionmolding a base housing for a plug base from a thermoplastic material,the base housing comprising a top side with a plurality of plug openingsand a continuous outer wall with a continuous recess disposed therein,and injection molding a continuous sealing ring from an elastomericmaterial into the recess of the outer wall of the base housing,providing a component comprising a plurality of plug pins and acomponent housing having a lower collar for matably receiving the basehousing therein, the lower collar having a continuous inside surface,inserting the component housing over the base housing and plug pins ofthe component into the plug openings so that the continuous sealing ringis deformably trapped between the inside surface of the collar of thecomponent housing and the recess of the outer wall of the base housing.